Welcome to the forum omn!

Almost every ex-muslim here has had similar thoughts and dilemmas about their faith at some point. So I hope you don't feel alone and hopeless.
All these thoughts can be overwhelming, I understand, but it helps to take a step back, and tackle one issue at a time.
Not everyone here is an atheist. There are those who still believe in God or some form of higher power, even if they have realised that religion is man made. Don't feel pressured to choose a belief system or try to put a label on it. Let your spiritual path decide itself as you learn more about various faiths and become comfortable with discovering your new thoughts and ideas. There are many personal stories here that can help you.
As for your family, it sounds like at the moment things are stable so maybe it's best not to rock the boat for now. Some members here have chosen to keep the peace and not reveal their lack of faith etc. at least until their children are grown up.
I have never been muslim, but I used to be a Christian, and I understand to some extent how difficult it is to keep up an appearance when you no longer believe. Praying and other things become very hard and sometimes you feel like you just want to burst out and tell everyone what is on your mind.
There are other more knowledgeable members here who can give you better advice, but stay positive and what you are going through is normal. I'm sure you will find a solution in time - a way to compromise both sides in a way that satisfies you and doesn't arouse unnecessary suspicion from other people.
May I ask if you live in a secular country?